Staple forming and driving mechanisms are known in which staples are formed and driven in one stroke. Examples of such devices are shown in U.S. Pat. Nos. 1,757,883, 2,659,885, 3,728,774 and 3,746,236, in all of which the staple is first cut from a coil of wire or a metal band, and then formed and driven. Furthermore, in all of these four patents separate linkages, levers, cams and the like connect the former and the driver to the source of power. That is, to say, except for the source of power, the former and driver have separate linkages due to the fact that the staple must be first formed and then driven. This leads to problems in that it requires a considerable number of moving parts and, further, the timing can be adversely effected with wear, such that the staple is not properly formed before driving.
In U.S. Pat. Nos. 3,009,156 and 3,690,537 staple formers and drivers are disclosed which form and drive a staple from a belt of staple blanks and which, moreover, operate the former from the driver which, in turn, is driven by the main drive source. Accordingly, in each of these U.S. Pat. Nos. 3,009,156 and 3,690,537 there is no separate linkage provided for the former and the driver but, rather, means is provided between the former and the driver so that after the staple has been formed, the former is disconnected from the driver and the driver continues on to drive the formed staple. Stated otherwise, there is a lost motion arrangement between the former and the driver. While these latter two staple formers and drivers do reduce the number of moving parts and the various linkages, they still have a very considerable number of moving parts and, in particular, the releasable connection between the former and driver is relatively complex.
Moreover, in all of such above mentioned staple former and driver devices, the number of parts with attendant pivots and the like require a relatively large housing even for driving the standard desk-type staple. Accordingly, up to the present time, most desk staplers have been of the type which merely drive pre-formed staples since the complications attendant upon forming as well as driving has heretofore involved a large number of parts, thus increasing costs both for raw materials and for assembly. Such costs have generally not been amenable to pricing such staple former and driving devices into the office market for use on desks by individuals.
Still further, with the complication of forming as well as driving, it will be appreciated that there is a greater tendency to jam the stapler. In all of the above, unjamming of the stapler can sometimes be accomplished merely by repeated strikes upon the operating knob but, at other times, some disassembly of the mechanism will be required to alleviate a jammed staple or staple blank condition.